I'd say the error message is pretty self-evident. It tells you it can't find the file 'runInstaller' in the current directory, and in your listing of the current directory there is no file named 'runInstaller'.

Exactly what product are you trying to install? What is the current directory you showed?

Actually, why are you trying to execute runInstaller.sh in the first place? The Installation Guide is pretty explicit. For example, if installing database 11.2, See http://docs.oracle.com/cd/E11882_01/install.112/e24321/inst_task.htm#BABJGGJH, where it says